JPH1135680A - Biodegradable polylatic acid esteramide and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biodegradable polylactic acid esteramide excellent in biodegradability, transparency and storage stability and capable of imparting dynamic strength and heat stability in response to uses, and to provide a method for producing the same. SOLUTION: This biodegradable polylactic acid esteramide has polyamide units of formula I: (NH-R1 -NHCO-R2 -CO) (R1 is a 1-13C divalent aliphatic alkylene group; R2 is a 4-12C linear alkylene group), polyester units of formula II: (O-R3 -OCO-R4 -CO) (R3 is a 2-10C aliphatic alkylene group; R4 is a 8-12C linear alkylene group), polylactic acid units of formula III: [CO-CH(CH3 )-O], and polylactone units of formula IV: (CO-R5 -O) (R5 is a 1-13C alkylene group) in a (Wa+Wb)/Wc ratio of 1/99 to 90/10 or in a (Wa+Wb)/(Wc+Wc') ratio of 1/99 to 90/10 (Ma is the molar number of the polyamide units; Mb is the mole number of the polyester units; Mc is the mole number of the polylactic acid units; Mc' is the mole number of the polylactone units).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel biodegradable polymer having controlled biodegradability, heat resistance and mechanical strength.

[0002]

2. Description of the Related Art Until now, biodegradable polymers such as aliphatic polyesters and natural polymers have been developed, but their common drawbacks are low heat resistance and low biodegradability. It is difficult to control, and research on polylactic acid and polyesteramide is being conducted recently. On the other hand, regarding the production method of polyesteramide, the following has been devised.

That is, a diol, a dicarboxylic acid, a diamine or a salt thereof is added and heated under reduced pressure.
(JP-B-3-63572, JP-B-63-4569)
No. 0), substituted morpholinedione or a derivative thereof is produced and polymerized. (Dee. Macromoleculare Hemi 1990, 191: 1813, etc.), a dicarboxylic acid or an anhydride thereof is reacted with a diamine to produce an oligomer having a carboxylic acid terminal and reacted with a diol (JP-A-2-124933). JP-A-5-82411), a polyester oligomer and a polyamide oligomer are mixed and esteramide exchange is carried out (JP-A-59-197429, JP-A-4-23).
No. 4458) and the like.

[0004] However, this method has a problem that the monomers used are limited and it is difficult to copolymerize with lactic acid or the like, which is expected to be biodegradable. Is a special reaction, such as the fact that it must be performed under highly diluted conditions, and is difficult to industrialize. In the method (1), the formation of the oligomer and the cyclization reaction become a competitive reaction, and the molecular weight hardly increases. This method is complicated and has problems such as difficulty in introducing lactic acid and the like.

[0005]

The problem to be solved by the present invention is that biodegradability, transparency, and storage stability are excellent, and biodegradation that can provide mechanical strength and heat resistance depending on the application. An object of the present invention is to provide a functional polylactic acid ester amide and a production method thereof.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, by copolymerizing lactide or lactide and lactones with polyesteramide, mechanical properties and the like have been improved. The present inventors have found that a biodegradable polylactic acid ester amide excellent in stability can be produced, and have reached the present invention.

That is, the present invention provides (1) a polyamide unit represented by the formula (1), a polyester unit represented by the formula (2), and a polylactic acid unit represented by the formula (3). Where the weight ratio of Wa, Wb, and Wc is (Wa + Wb) / Wc, 1/99 to 90/10
A biodegradable polylactic acid ester amide,

(-NH-R ₁ -NHCO-R ₂ -CO-) wherein R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms;
R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms)

(-OR ₃ -OCO-R ₄ -CO-) wherein R ₃ is an aliphatic alkylene group having 2 to 10 carbon atoms;
R ₄ represents an aliphatic alkylene group having 8 to 12 carbon atoms)

(Formula 3) (—CO—CH (CH ₃ ) —O—)

(2) It has a polyamide unit represented by the chemical formula 1, a polyester unit represented by the chemical formula 2, a polylactic acid unit represented by the chemical formula 3, and a polylactone unit represented by the chemical formula 4. , And the weight ratio of each unit is W
a, Wb, Wc, Wc ′, (Wa + Wb) /
A biodegradable polylactic acid ester amide having a value of (Wc + Wc ′) of 1/99 to 90/10,

(-NH-R ₁ -NHCO-R ₂ -CO-) wherein R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms;
R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms)

(-OR ₃ -OCO-R ₄ -CO-) wherein R ₃ is an aliphatic alkylene group having 2 to 10 carbon atoms;
R ₄ represents an aliphatic alkylene group having 8 to 12 carbon atoms)

(Formula 3) (—CO—CH (CH ₃ ) —O—)

(Formula 4) (-OR ₅ -CO-) wherein R ₅ represents an alkylene group having 1 to 13 carbon atoms.

(3) It has a polyamide unit represented by the formula (1) and a polyester unit represented by the formula (2), and Ma / Mb is 50 when the number of moles is Ma and Mb, respectively.
A method for producing a biodegradable polylactic acid ester amide, comprising subjecting a lactide to ring-opening polymerization to a polyesteramide having a ratio of / 50 or less,

(-NH-R ₁ -NHCO-R ₂ -CO-) wherein R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms;
R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms)

(-OR ₃ -OCO-R ₄ -CO-) wherein R ₃ is an aliphatic alkylene group having 2 to 10 carbon atoms;
R ₄ represents an aliphatic alkylene group having 8 to 12 carbon atoms)

(4) It has a polyamide unit represented by the formula (1) and a polyester unit represented by the formula (2), and Ma / Mb is 50 when the respective moles are Ma and Mb.
A method for producing a biodegradable polyester amide, comprising subjecting a polyester amide having a molecular weight of / 50 or less to ring-opening polymerization of a lactide and a lactone forming the chemical formula 4, and

(-NH-R ₁ -NHCO-R ₂ -CO-) wherein R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms;
R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms)

(-OR ₃ -OCO-R ₄ -CO-) wherein R ₃ is an aliphatic alkylene group having 2 to 10 carbon atoms;
R ₄ represents an aliphatic alkylene group having 8 to 12 carbon atoms)

(Formula 4) (—O—R ₅ —CO—) (R ₅ represents an alkylene group having 1 to 13 carbon atoms)

(5) A polyamide unit represented by the chemical formula 1, a polyester unit represented by the chemical formula 2, and
Having a polylactone unit represented by the formula,
Ma when the number of moles of each unit in the formula is Ma and Mb
/ Mb is 50/50 or less polyester amide,
The method includes a method for producing a biodegradable polyester amide, which comprises subjecting a lactone represented by the formula (4) to ring-opening polymerization.

(Formula 1) (—NH—R ₁ —NHCO—R ₂ —CO—) (R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms, and R ₂ is an aliphatic alkylene group having 4 to 12 carbon atoms) Represents a group)

(-OR ₃ -OCO-R ₄ -CO-) wherein R ₃ is an aliphatic alkylene group having 2 to 10 carbon atoms, and R ₄ is an aliphatic alkylene group having 8 to 12 carbon atoms. (Representing a group) (Formula 4) (-OR ₅ -CO-) (R ₅ represents an alkylene group having 1 to 13 carbon atoms)

[0026]

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyamide unit represented by the formula (1), a polyester unit represented by the formula (2), a polylactic acid unit represented by the formula (3) and, if necessary, a formula (4). Having a polylactone unit represented,
When the weight ratio of the units of the formulas 1, 2, 3 and 4 is Wa, Wb, Wc and Wc ′, (Wa + W
b) A biodegradable polyesteramide having a value of / (Wc + Wc ′) of 1/99 to 90/10.

(-NH-R ₁ -NHCO-R ₂ -CO-) wherein R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms;
R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms)

(-OR ₃ -OCO-R ₄ -CO-) wherein R ₃ is an aliphatic alkylene group having 2 to 10 carbon atoms;
R ₄ represents an aliphatic alkylene group having 8 to 12 carbon atoms)

(Formula 3) (—CO—CH (CH ₃ ) —O—)

As the diamine constituting the polyamide unit (A), any diamine may be used as long as it is an aliphatic diamine having 13 or less carbon atoms. The diamine may be linear, branched or alicyclic. Any of those having a hetero atom may be used, and examples thereof include ethylenediamine, propylenediamine, tetramethylenediamine, hexamethylenediamine, octamethylenediamine,

Examples include decamethylenediamine, trimethylhexamethylenediamine, isophoronediamine, bis (aminocyclohexyl) methane, hydrogenated xylylenediamine, hydrogenated toluylenediamine, diaminodiethylether and the like. Particularly preferred are diamines having 6 to 13 carbon atoms. By using such a diamine, the molecular weight can be easily improved as compared with other systems. In addition, heat resistance and biodegradability can be improved partially or entirely using an alicyclic diamine or a diamine having an ether bond, a thioether bond, or a sulfone bond.

As the dicarboxylic acid constituting the polyamide unit (A), any of dicarboxylic acids having a carbon number of R ₂ of 4 to 12 can be used, and particularly those having a carbon number of R ₂ of 6 to 12 can be used. Is preferred. To illustrate them,
Suberic acid, nonanedicarboxylic acid, sebacic acid, dodecanedicarboxylic acid and the like. By selecting such a material, a relatively inexpensive high molecular weight polyesteramide can be obtained.

As the diol constituting the polyester unit (B), any one can be used as long as it has 2 to 10 carbon atoms of R ₃ , but those having 2 to 8 carbon atoms of R ₃ are particularly preferable. Examples thereof include ethylene glycol, propylene glycol, tetramethylenediol, 1,3-butanediol, hexamethylenediol, octamethylenediol, cyclohexanedimethanol, neopentyl glycol and the like.

From the viewpoint that a high molecular weight product can be easily obtained, it is desirable that a diol having a relatively low boiling point such as ethylene glycol, propylene glycol, or tetramethylene diol is contained as a component. When producing such a polyester containing no diol, the diol is driven out by transesterification, so that a polyester having a higher molecular weight can be produced.

As the dicarboxylic acid constituting the polyester unit (B), any one can be used as long as R ₄ has 4 to 12 carbon atoms. Examples thereof include adipic acid, suberic acid and sebacine. Acid, decanedicarboxylic acid, dodecanedicarboxylic acid, cyclohexanedicarboxylic acid and the like. In particular, when obtaining a high-molecular-weight and high-strength lactic acid-containing biodegradable polyesteramide, it is preferable that R ₄ be a dicarboxylic acid having a linear aliphatic alkylene group having 6 to 12 carbon atoms.

The diols, dicarboxylic acids, and diamines described above can be used alone, but two or more of them can be used in combination to obtain more satisfactory physical properties. For example, by partially adding a branched diol or a diol having a different methylene chain length,
Transparency and crystallinity can be further improved.
By mixing more than one kind of diamine, transparency can be further improved without lowering heat resistance.

In the production of the polyesteramide, lactones such as caprolactone, lactams such as caprolactam, polyethers such as polyethylene glycol and polytetramethylene glycol, trimethylolethane, glycerin, and the like, as long as polymerization is not inhibited. Polyhydric alcohols such as pentaerythritol, pyromellitic acid or anhydride thereof, polycarboxylic acids and anhydrides thereof such as trimellitic anhydride, hexamethylene diisocyanate and isophorone diisocyanate, and diisocyanate compounds such as hydrogenated diphenylmethane diisocyanate. A unit capable of further improving the molecular weight may be added.

In particular, when it is desired to increase the molecular weight of the polyester amide, it is preferable to use a diisocyanate compound. When bleed out from a molded product occurs due to poor compatibility between the polyamide unit and the polyester unit, a lactone is preferably used. And lactams are preferably added.

As a method for producing a polyesteramide, a method of directly mixing a dicarboxylic acid, a diol, and a diamine, and a method of adding a dicarboxylic acid, a diol, and a diamine / dicarboxylic acid salt are preferably used. It is preferable to use a dicarboxylic acid, a diol, or a salt of a dicarboxylic acid / diamine in that the formation of oligomers is reduced and the copolymerization of polyesteramide with lactide or lactone proceeds smoothly. It is also possible to replace a part thereof with another derivative such as an oligomer of polyester or polyamide.

In this case, the molar ratio of the substantial diol to the diamine is (the total molar number of the diol) / (the total molar number of the diamine), preferably 50/50 to 95/5. Hereinafter, more preferably, 60 /
It is 40 or more and 90/10 or less. By setting such a ratio, it is possible to obtain a suitable precursor polyesteramide which gives a biodegradable polyesteramide having a good balance of biodegradability, transparency, strength, melt viscosity and the like. However, the term "substantially the total number of moles" as used herein refers to the sum of diols, diamines alone, polyester oligomers, polyamide oligomers, and carboxylate salts.

On the other hand, in producing the polyester amide, the sum of the number of moles of the diol and the diamine is desirably set to 105 compared with the number of moles of the dicarboxylic acid.
% To 150%, more preferably 110% to 13
It is desirable to set it to 0% or less. After dehydration is caused by setting the amount to such an amount, a catalyst is added and the polymerization is allowed to proceed by a transesterification reaction, whereby a high molecular weight precursor polyesteramide can be obtained.

The catalyst used at this time may be a conventional one such as a germanium-based, titanium-based, antimony-based, tin-based, zinc-based, or lead-based catalyst, and is particularly preferably a titanium-based catalyst. Alkoxides such as titanium tetraisopropoxide and titanium tetrabutoxide can be used. As the reaction temperature, the usual conditions for producing polyester can be used. Specifically, preferably 120 to 300 ° C, more preferably 150 to 260 ° C,
Further, it is desirable to reduce the pressure as the temperature is increased.

In the production of polylactic acid ester amide, it can be produced by reacting a precursor polyesteramide with lactide or a mixture of lactone and lactide, or simultaneously with a polyesteramide constituent and lactic acid, lactone or an oligomer thereof. In addition, it can be produced, but is obtained by reacting a precursor polyesteramide with a lactide or a reaction between a precursor polyesteramide and a lactide / lactone mixture in that a transparent polymer having no stickiness due to oligomers or the like can be obtained. Is desirable.

Here, the weight ratio of the polyesteramide to the lactide is such that the weights of the polyamide component (A), the polyester component (B) and the polylactic acid unit (C) in the produced biodegradable polyesteramide are Wa and Wb. ,
When Wc, the value of (Wa + Wb) / Wc is 1/99.
It is preferably at least 90/10 or less, and particularly preferably at least 1/99 or more and 80/20 or less.

The ratio of L-form to D-form of lactide (F),
Any L / D ratio can be used, but in the case of lactide alone, the L / D ratio is preferably from 70/30 to 99/1. By doing so, a biodegradable polyesteramide having excellent strength at normal temperature can be provided. It is also possible to replace part of the lactide with another lactone, and in this way 6
It is also possible to alleviate a sharp decrease in strength due to polylactic acid occurring at around 0 ° C. When producing such a biodegradable polyesteramide, the L / D ratio is 30/70 to 99 /
1 is desirable. By using such a ratio, it is possible to further alleviate a sharp decrease in strength derived from polylactic acid at a higher temperature.

As such a lactone, any lactone giving the formula (4) by ring-opening polymerization may be used. Examples thereof include caprolactone, propiolactone, butyrolactone, valerolactone, glycolide, and the like. Examples thereof include 1,5-dioxepan-2-one and the like. Among them, lactones having 4 or less member rings or 7 or more member rings are preferable, and ε-caprolactone, 1,5-
Dioxepan-2-one and the like are desirable.

The weight ratio of lactide to lactone to be added to the precursor polyesteramide varies depending on the nature of the precursor polyesteramide. In particular, when an elastic modulus at room temperature is required and shape stability during heating is not required, Wf / Wg is 80/2 when each weight is Wf and Wg.
For applications not less than 0, especially at room temperature, which are flexible and do not decrease in strength even when heated, they can be used properly, such as Wf / Wg of 10/90 to 80/20.

Further, lactide alone and lactide /
The catalyst used when copolymerizing a lactone mixture with polyesteramide is used for ordinary polyester synthesis such as titanium, zinc, germanium, aluminum, lead, tin, antimony, lanthanoid, and rare earth metal. Any of these can be suitably used, but a tin-based catalyst is particularly preferable, and tin octoate, stannous chloride, stannous oxide and the like are preferably used.

[0049]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. The number average molecular weight (hereinafter abbreviated as Mn),
The weight average molecular weight (hereinafter abbreviated as Mw) was measured by GPC using chloroform as a solvent and monodispersed polystyrene as a standard substance.

The storage stability test was performed unless otherwise specified.
A 250 micron thick sheet pressed at 170 ° C. for 2 minutes was stored at 35 ° C. and 80% humidity for observation. In addition, Izod impact strength was measured using an Izod impact tester manufactured by Custom Scientific Instruments, and dynamic viscoelasticity measurement was performed by using a part of a sheet formed for storage stability test. Height 36
mm (however, the distance between clamps is 22.6 mm), 5 mm wide
And measured using Rheometrics RSAII.

The biodegradability test was carried out on a 10
Use 0 liter Shinki Gosei Co., Ltd. composting container Tonbo Miracle Component 100 type, put 50 kg of garbage, put the created film, and further garbage about 5 cm
It was put in the thickness of about. On top of that, 500 g of Aronkaseisha's fermentation accelerator Nyuxaminon was sprinkled and evaluated.
The device was installed outdoors. Specimens were observed every 7 days.

(Reference Example 1) 113.1 g of sebacic acid
(0.560 mol), 44.6 g of ethylene glycol
(0.719 mol), 76.32 g (0.240 mol) of sebacic acid-hexamethylenediamine salt were charged into a separable flask equipped with stirring blades, and after purging with nitrogen, the temperature was raised to 190 ° C. while stirring. While holding for 5 hours,
A dehydration reaction was caused by a stream of nitrogen. After cooling, 100 mg of titanium tetraisopropoxide was added,
200 ° C, 200 Torr, 250 ° C over 6 hours
And reduced the pressure to 0.1 Torr. After allowing it to react for 4 hours, the pressure was returned to normal pressure, and the resin was taken out. Mn of the obtained resin was 8,800 and Mw was 1,980.
It was 0.

Example 1 The polyesteramide obtained in Reference Example 1 was placed in a separable flask equipped with stirring blades.
After adding 0 g, 8.0 g of DL-lactide, 8.0 g of ε-caprolactone, and 30 ml of toluene, stirring and homogenizing, 52 mg of tin octoate was added, and polymerization was performed at 170 ° C. for 5 hours. Mn of the obtained polymer was 38.
500, Mw was 72,700, and the residual monomers were ε-caprolactone at 1.6% and lactide at 1.5%.

This polymer was cast into a film using chloroform as a solvent, washed with acetone, dried in a vacuum oven at 90 ° C. to remove unreacted monomers, and measured for IR spectrum and proton NMR spectrum. , Izod test, dynamic viscoelasticity measurement, storage stability test. As a result of IR spectrum measurement, amide I:
From absorption around 1630 cm ^-1, absorption near 1540 cm ^-1 derived from an amide II, confirmed the formation of polyesteramides from absorption derived from carbonyl stretching vibration of the polyester in the vicinity of 1730 cm ^-1, The proton NM
From the result of the measurement of R, it was confirmed that a polylactic acid ester amide having a composition of a predetermined ratio could be produced.

FIG. 1 shows the obtained proton NMR chart.
Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement. As a result of the storage stability test, a white powdery bleed-out foreign substance was observed in 96 days. As a result of the biodegradability test, it became brittle in 49 days, and could not keep its original form in 77 days.

Example 2 The procedure of Example 1 was repeated using 16.0 g of the polyesteramide obtained in Reference Example 1, 8.0 g of L-lactide, 8.0 g of ε-caprolactone, 30 ml of toluene and 52 mg of tin octoate. Polymerized. Mn of the obtained polymer was 37,400 and Mw was 7,060.
0, the residual monomer was 1.4% ε-caprolactone and 1.9% lactide. This polymer was prepared in Example 1.
Purified in the same manner as in
Spectrum measurement, Izod test, dynamic viscoelasticity measurement,
It was subjected to a storage stability test. From the results of the IR spectrum and the proton NMR measurement, it was confirmed that a polylactic acid ester amide having a predetermined composition ratio was produced in the same manner as in Example 1. As a result of the storage stability test, a white powdery bleed-out foreign substance was observed at 94 days. Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement. In addition, as a result of the biodegradability test, it became brittle in 49 days and could not keep its original form in 70 days.

Example 3 The polyesteramide obtained in Reference Example 1 was placed in a separable flask equipped with stirring blades.
0 g, L-lactide 34.3 g, D-lactide 0.
Polymerization was carried out in the same manner as in Example 1 using 7 g and 20 ml of toluene. Mn of the obtained polymer was 5170.
0, Mw was 99,900, and residual lactide was 3.2%. This polymer was purified as in Example 1,
Measurement of IR spectrum and proton NMR spectrum,
It was subjected to an Izod test, a dynamic viscoelasticity measurement, and a storage stability test. From the result of the IR spectrum measurement and the result of the proton NMR spectrum, formation of polylactic acid ester amide having a predetermined ratio was confirmed. In addition, as a result of the storage stability test, white powdery bleed-out foreign substances came to be seen in 85 days. Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement. The results of the biodegradability test showed that the sample became brittle at 49 days and could not keep its original form at 77 days.

(Reference Example 2) 113.1 g of sebacic acid
(0.560 mol), 44.6 g of ethylene glycol
(0.719 mol), 76.32 g (0.24 mol) of sebacic acid-hexamethylenediamine salt were charged into a separable flask, and after purging with nitrogen, the mixture was stirred for 190 minutes.
The temperature was raised to ° C., and a dehydration reaction was caused by a stream of nitrogen while maintaining the temperature for 5 hours. After cooling, 100 mg of titanium tetraisopropoxide and 1 of ε-caprolactone were added.
2.76 g (0.111 mol) was added, and 200 ° C., 200
From Torr, the temperature was raised to 250 ° C. over 6 hours,
The pressure was reduced to 1 Torr. After allowing it to react for 4 hours, the pressure was returned to normal pressure, and the resin was taken out. Mn of the obtained resin was 11,300. Mw was 24,500.

Example 4 The procedure of Example 1 was repeated using 15.0 g of the polyesteramide obtained in Reference Example 2, 34.3 g of L-lactide, 0.7 g of D-lactide, 50 ml of toluene and 50 mg of tin octoate. And synthesized.
Mn of the obtained polymer was 47,800 and Mw was 9,430.
0, the residual lactide was 2.7%. This polymer was purified in the same manner as in Example 1 and subjected to measurement of IR spectrum and proton NMR spectrum, and Izod test, dynamic viscoelasticity measurement and storage stability test. From the results of the IR spectrum and the proton NMR measurement, it was confirmed that a polylactic acid ester amide having a predetermined composition ratio was produced in the same manner as in Example 1. In addition, as a result of the storage stability test, white powdery bleed-out foreign substances were observed in 90 days. Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement. The result of the biodegradability test was 42
It became brittle in a day, and could not keep its prototype in 70 days.

Example 5 The procedure of Example 1 was repeated using 16.0 g of the polyesteramide obtained in Reference Example 2, 8.0 g of L-lactide, 8.0 g of ε-caprolactone, 30 ml of toluene and 50 mg of tin octoate. And synthesized. Mn of the obtained polymer was 44400 and Mw was 9
3,700, 2.8% residual lactide, 1.0% residual ε-caprolactone. This polymer was prepared in Example 1.
Purification was carried out in the same manner as in
It was subjected to the measurement of the R spectrum, the Izod test, the dynamic viscoelasticity measurement and the storage stability test. From the results of the IR spectrum and the proton NMR measurement, it was confirmed that a polylactic acid ester amide having a predetermined composition ratio was produced in the same manner as in Example 1. In addition, as a result of storage stability test, 94
In the day, white powdery bleed-out foreign substances began to be seen. Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement. The results of the biodegradability test showed that the sample became brittle at 42 days and could not keep its original form at 77 days.

Example 6 16.0 g of the polyesteramide obtained in Reference Example 2, 4.0 g of L-lactide, 4.0 g of D-lactide, 8.0 g of ε-caprolactone, 30 ml of toluene and 50 mg of tin octoate were used. Example 1
Synthesis was performed in the same manner as described above. The Mn of the obtained polymer was 52,000, the Mw was 95,300, and the residual lactide was 2.
8% and residual ε-caprolactone were 1.0%. This polymer was purified in the same manner as in Example 1 and subjected to measurement of IR spectrum and proton NMR spectrum, and Izod test, dynamic viscoelasticity measurement and storage stability test.

From the results of the IR spectrum and the proton NMR measurement, it was confirmed that a polylactic acid ester amide having a predetermined composition was produced in the same manner as in Example 1.
Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement.
As a result of the storage stability test, white powdery bleed-out foreign substances came to be seen in 104 days. The results of the biodegradability test showed that the material became brittle at 42 days and did not remain in the original form at 70 days.

(Reference Example 3) 169.6 g of sebacic acid
(0.840 mol), 54.56 g of ethylene glycol
(0.88 mol), 13.6 g of isophoronediamine
(0.080 mol) in a separable flask,
After the replacement with nitrogen, the temperature was raised to 190 ° C. with stirring, and while maintaining the temperature for 5 hours, a dehydration reaction was caused by a stream of nitrogen. After cooling, 1 part of titanium tetraisopropoxide was added.
After adding 200 mg, the temperature was raised from 200 ° C. and 200 Torr to 250 ° C. over 6 hours, and the pressure was reduced to 0.1 Torr. After allowing it to react for 4 hours, the pressure was returned to normal pressure and the resin was taken out. Mn of the obtained resin was 15400,
Mw was 37,800.

Example 7 The polyesteramide obtained in Reference Example 3 was placed in a separable flask equipped with stirring blades.
0 g, L-lactide 34.3 g, D-lactide 0.
7 g, hexamethylene diisocyanate 0.163 g,
After adding 15 ml of toluene and stirring to homogenize,
50 mg of tin octoate was added and polymerization was carried out at 170 ° C. for 5 hours. Mn of the obtained polymer was 40500, M
w was 71,800 and the residual lactide was 2.2%.

The polymer was cast into a film using chloroform as a solvent, washed with acetone, and dried in a vacuum oven at 90 ° C. to remove unreacted monomers.
Measurement of IR spectrum and proton NMR spectrum,
And Izod test, dynamic viscoelasticity measurement and storage stability test. As a result of the storage stability test, a white powdery bleed-out foreign substance came to be seen in 85 days. IR
From the results of the spectrum and proton NMR measurements, it was confirmed that a polylactic acid ester amide having a predetermined composition ratio was produced in the same manner as in Example 1. Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement. Further, the result of the biodegradability test became brittle in 63 days.

Example 8 The polyesteramide obtained in Reference Example 3 was placed in a separable flask equipped with stirring blades.
0 g, L-lactide 8.0 g, ε-caprolactone 8.0 g, hexamethylene diisocyanate 0.173
g and 30 ml of toluene, and the mixture was stirred at 170 ° C. to make the mixture uniform, and then 50 mg of tin octoate was added to add 17 mg.
Polymerization was performed at 0 ° C. for 5 hours. Mn of the obtained polymer
Was 41300, Mw was 72400, residual lactide was 1.5%, and residual ε-caprolactone was 1.7%.

The polymer was cast into a film using chloroform as a solvent, washed with acetone, and dried in a vacuum oven at 90 ° C. to remove unreacted monomers.
Measurement of IR spectrum and proton NMR spectrum,
And Izod test, dynamic viscoelasticity measurement and storage stability test. From the results of the IR spectrum and proton NMR measurements, it was confirmed that a lactic acid-containing polyesteramide having a predetermined composition was produced in the same manner as in Example 1. In addition, as a result of the storage stability test, a white powdery bleed-out foreign substance was found to be observed at 94 days. Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement. In addition, the result of the biodegradability test showed that the sample became brittle at 56 days and could not keep its original form at 77 days.

Reference Example 4 127.2 g of sebacic acid
(0.630 mol), 40.92 g of ethylene glycol
(0.66 mol), bis (4-aminocyclohexyl)
12.6 g (0.06 mol) of methane was charged into a separable flask, and the mixture was purged with nitrogen.
While maintaining the temperature for 5 hours, a dehydration reaction was caused by a stream of nitrogen. After cooling, 100 mg of titanium tetraisopropoxide was added, and 200 ° C., 200 Torr
r to 250 ° C. over 6 hours, and 0.1 To
The pressure was reduced to rr. After allowing it to react for 4 hours, the pressure was returned to normal pressure, and the resin was taken out. M of the obtained resin
n was 9800 and Mw was 37600.

(Example 9) The polyesteramide obtained in Reference Example 4 was placed in a separable flask equipped with stirring blades.
0 g, L-lactide 34.3 g, D-lactide 0.
7 g, hexamethylene diisocyanate 0.163 g,
After adding 15 ml of toluene and stirring to homogenize,
50 mg of tin octoate was added and polymerized at 170 ° C. for 5 hours. Mn of the obtained polymer was 37,200, Mw was 74,300, and residual lactide was 2.9%.

This polymer was cast into a film using chloroform as a solvent, washed with acetone, and dried in a vacuum oven at 90 ° C. to remove unreacted monomers.
Measurement of IR spectrum and proton NMR spectrum,
And Izod test, dynamic viscoelasticity measurement and storage stability test. From the results of the IR spectrum and proton NMR measurements, it was confirmed that a lactic acid-containing polyesteramide having a predetermined composition was produced in the same manner as in Example 1. In addition, as a result of the storage stability test, a white powdery bleed-out foreign substance was observed in 96 days. Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement. Further, the result of the biodegradability test became brittle in 56 days.

Example 10 Polyesteramide 1 obtained in Reference Example 4 was placed in a separable flask equipped with stirring blades.
After adding 6.0 g, 8.0 g of L-lactide, 8.0 g of ε-caprolactone and 30 ml of toluene and stirring at 170 ° C. to homogenize, 50 mg of tin octanoate was added and polymerized at 170 ° C. for 5 hours. Was done. Mn of the obtained polymer was 38,400, Mw was 75,000, residual lactide was 1.9%, and residual ε-caprolactone was 1.4%.

This polymer was cast into a film using chloroform as a solvent, washed with acetone, and dried in a vacuum oven at 90 ° C. to remove unreacted monomers.
Measurement of IR spectrum and proton NMR spectrum,
And Izod test, dynamic viscoelasticity measurement and storage stability test. From the results of the IR spectrum and proton NMR measurements, it was confirmed that a lactic acid-containing polyesteramide having a predetermined composition was produced in the same manner as in Example 1. In addition, as a result of the storage stability test, a white powdery bleed-out foreign substance was observed in 102 days. Table 1 shows the results of the Izod test and the dynamic viscoelasticity measurement. Further, the result of the biodegradability test became brittle in 56 days.

Reference Example 5 84.8 g of adipic acid (0.
420 mol), 31.02 g of ethylene glycol (0.
50 mol), ethylenediamine 10.44 g (0.71
4 mol) was placed in a separable flask, and after purging with nitrogen, the temperature was raised to 190 ° C. with stirring, and while maintaining the temperature for 5 hours, a dehydration reaction was caused by a stream of nitrogen. After cooling, 100 mg of titanium tetraisopropoxide was added, and 25 ° C. at 200 ° C. and 200 Torr for 6 hours.
The temperature was raised to 0 ° C., and the pressure was reduced to 0.1 Torr. After allowing it to react for 4 hours, the pressure was returned to normal pressure, and the resin was taken out. Mn of the obtained resin was 1630 and Mw was 12
400.

Comparative Example 1 The polyesteramide obtained in Reference Example 5 was placed in a separable flask equipped with stirring blades.
0 g, L-lactide 34.3 g, D-lactide 0.
7 g and toluene (about 30 ml) were added, and the mixture was stirred to make the mixture uniform.
Polymerization was performed for a time. Mn of the obtained polymer was 450.
0, Mw was 23,500, and residual lactide was 3.2%. This polymer is cast into a film using chloroform as a solvent, washed with acetone, dried in a vacuum oven at 90 ° C. to remove unreacted monomers, and then subjected to Izod test, dynamic viscoelasticity measurement and storage stability test. Was served.
As a result of the storage stability test, a white powdery bleed-out foreign substance was observed in 34 days. Table 2 shows the results of the Izod test and the dynamic viscoelasticity measurement.

(Comparative Example 2) The polyesteramide obtained in Reference Example 5 was placed in a separable flask equipped with stirring blades.
0 g, 8.0 g of L-lactide, 8.0 g of ε-caprolactone, and about 30 ml of toluene. The mixture was stirred at 170 ° C. to be uniform, and then 50 mg of tin octoate was added. went. Mn of the obtained polymer was 4,700, Mw was 24,200, and residual lactide was 2.9%. This polymer is cast into a film using chloroform as a solvent, washed with acetone, dried in a vacuum oven at 90 ° C. to remove unreacted monomers, and then subjected to Izod test, dynamic viscoelasticity measurement and storage stability test. Was served. As a result of the storage stability test, a white powdery bleed-out foreign substance was observed in 25 days. Table 2 shows the results of the Izod test and the dynamic viscoelasticity measurement.

Reference Example 6 113.1 g of sebacic acid
(0.560 mol), 44.6 g of ethylene glycol
(0.719 mol) in a separable flask,
After the replacement with nitrogen, the temperature was raised to 190 ° C. with stirring, and while maintaining the temperature for 5 hours, a dehydration reaction was caused by a stream of nitrogen. After cooling, 1 part of titanium tetraisopropoxide was added.
After adding 200 mg, the temperature was raised from 200 ° C. and 200 Torr to 250 ° C. over 6 hours, and the pressure was reduced to 0.1 Torr. After allowing it to react for 4 hours, the pressure was returned to normal pressure, and the resin was taken out. Mn of the obtained resin was 3,800.
0 and Mw were 63,000.

Comparative Example 3 15.0 g of the polyester obtained in Reference Example 6 was placed in a separable flask equipped with stirring blades.
34.3 g of L-lactide, 0.7 g of D-lactide,
After adding 30 ml of toluene and stirring to homogenize,
50 mg of tin octoate was added and polymerization was carried out at 170 ° C. for 5 hours. Mn of the obtained polymer was 45900, M
w was 103000 and the residual lactide was 3.3%. This polymer is cast into a film using chloroform as a solvent, washed with acetone, dried in a vacuum oven at 90 ° C. to remove unreacted monomers, and then subjected to Izod test, dynamic viscoelasticity measurement and storage stability test. Was served. As a result of the storage stability test, a white powdery bleed-out foreign substance was observed in 95 days. Table 2 shows the results of the Izod test and the dynamic viscoelasticity measurement.

Table 1 shows Examples 1 to 10, and Table 2 shows Comparative Examples 1 to
Izod test of the polymer obtained in 3 (notched, unit:
kJ / m ² ) and the results of a dynamic viscoelasticity test and a storage stability test. Izod strength as impact resistance is usually 10
It is preferable that there is the above. Those with an Izod test value of 60 or more were unmeasurable, and the upper limit was described. Tt is the temperature at which the storage elastic modulus starts to decrease (unit:
° C) and those which cannot be detected mechanically are N.I. D. E'20 is the storage modulus at 20 ° C. (unit: k
g / cm ² ) and E′80 indicate the storage modulus at 80 ° C. (unit: kg / cm ² ), and E′20 is 10,000.
The above are relatively hard resins, E'20 / E '
The lower the value of 80, the better the thermal stability.
The storage stability was such that a bleed-out was 80 in the storage stability test.
Those that were not seen for more than days were rated as ○, and those that were between 30 days and less than 80 days were rated as Δ.

[0079]

[Table 1]

[0080]

[Table 2]

From Tables 1 and 2, it can be seen that the biodegradable polylactic acid ester amide of the present invention is excellent in biodegradability, impact resistance and storage stability. It can be seen that the mechanical strength is improved as compared with the polyester itself or the polyester, whereas the copolymer of polyesteramide, lactide and lactone has particularly improved heat resistance.

[0082]

According to the present invention, a high molecular weight biodegradable, transparent, and mechanical strength (particularly impact resistance) can be obtained by copolymerizing polyesteramide and lactide or a lactide / lactone mixture. A biodegradable polylactic acid ester amide excellent in heat resistance and storage stability can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a proton NMR measurement result of a biodegradable polylactic acid ester amide obtained in Example 1 of the present invention.

Claims (5)

[Claims] 1. A polyamide unit represented by the formula:
When having a polyester unit represented by the formula (2) and a polylactic acid unit represented by the formula (3), and the weight ratio of each unit is defined as Wa, Wb, and Wc, (Wa + Wb) /
A biodegradable polylactic acid ester amide having a value of Wc of 1/99 to 90/10. (Formula 1 _{Formula) (-NH-R 1 -NHCO-} R 2 -CO-) ( wherein, R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms,
R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms. (Formula 2) (-OR ₃ -OCO-R ₄ -CO-) (wherein, R ₃ is an aliphatic having 2 to 10 carbon atoms) Group alkylene group,
R ₄ represents an aliphatic alkylene group having 8 to 12 carbon atoms. (Formula 3) (—CO—CH (CH ₃ ) —O—) 2. A polyamide unit represented by the formula:
It has a polyester unit represented by Chemical Formula 2, a polylactic acid unit represented by Chemical Formula 3, and a polylactone unit represented by Chemical Formula 4, and the weight ratio of each unit is Wa;
When Wb, Wc, and Wc ′, (Wa + Wb) / (W
c + Wc ′) is a biodegradable polylactic acid ester amide having a value of 1/99 to 90/10. (Formula 1 _{Formula) (-NH-R 1 -NHCO-} R 2 -CO-) ( wherein, R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms,
R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms. (Formula 2) (-OR ₃ -OCO-R ₄ -CO-) (wherein R ₃ is an aliphatic having 2 to 10 carbon atoms) Group alkylene group,
R ₄ represents an aliphatic alkylene group having 8 to 12 carbon atoms. (Formula 3) (—CO—CH (CH ₃ ) —O—) (Formula 4) (—O—R ₅ —CO—) ( In the formula, R ₅ represents an alkylene group having 1 to 13 carbon atoms) 3. A polyamide unit represented by the formula:
Ma / Mb is 50/5 when the number of moles is Ma and Mb.
A process for producing a biodegradable polylactic acid ester amide, comprising subjecting a lactide to ring-opening polymerization with a polyesteramide having a value of 0 or less. (Formula 1 _{Formula) (-NH-R 1 -NHCO-} R 2 -CO-) ( wherein, R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms,
R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms. (Formula 2) (-OR ₃ -OCO-R ₄ -CO-) (wherein, R ₃ is an aliphatic having 2 to 10 carbon atoms) Group alkylene group,
R ₄ represents an aliphatic alkylene group having 8 to 12 carbon atoms) 4. A polyamide unit represented by the formula:
Ma / Mb is 50/5 when the number of moles is Ma and Mb.
A process for producing a biodegradable polyester amide, which comprises subjecting a polyester amide having a molecular weight of 0 or less to ring-opening polymerization of a lactide and a lactone forming the formula (4). (Formula 1 _{Formula) (-NH-R 1 -NHCO-} R 2 -CO-) ( wherein, R ₁ is an aliphatic alkylene group having 1 to 13 carbon atoms,
R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms. (Formula 2) (-OR ₃ -OCO-R ₄ -CO-) (wherein, R ₃ is an aliphatic having 2 to 10 carbon atoms) Group alkylene group,
R ₄ represents an aliphatic alkylene group having 8 to 12 carbon atoms. (Formula 4) (—O—R ₅ —CO—) (R ₅ represents an alkylene group having 1 to 13 carbon atoms) 5. A polyamide unit represented by the formula:
Ma / M having a polyester unit represented by Chemical Formula 2 and a polylactone unit represented by Chemical Formula 4, wherein the number of moles of each unit of Chemical Formula 2 is Ma and Mb.
A process for producing a biodegradable polyesteramide, comprising subjecting a polyesteramide having b of 50/50 or less to ring-opening polymerization of a lactide and a lactone represented by the formula (4). (Formula 1) (—NH—R ₁ —NHCO—R ₂ —CO—) (R ₁ represents an aliphatic alkylene group having 1 to 13 carbon atoms, and R ₂ represents an aliphatic alkylene group having 4 to 12 carbon atoms.) (Formula 2) (—OR ₃ —OCO—R ₄ —CO—) (R ₃ is an aliphatic alkylene group having 2 to 10 carbon atoms, and R ₄ is an aliphatic alkylene group having 8 to 12 carbon atoms) (Formula 4) (-OR ₅ -CO-) (R ₅ represents an alkylene group having 1 to 13 carbon atoms)